Aims. Radiological residual acetabular dysplasia (RAD) has been reported in up to 30% of children who had successful brace treatment of infant developmental dysplasia of the hip (DDH). Predicting those who will resolve and those who may need corrective surgery is important to optimize follow-up protocols. In this study we have aimed to identify the prevalence and predictors of RAD at two years and five years post-bracing. Methods. This was a single-centre, prospective longitudinal cohort study of infants with DDH managed using a published, standardized Pavlik harness protocol between January 2012 and December 2016. RAD was measured at two years’ mean follow-up using acetabular index-lateral edge (AI-L) and acetabular index-sourcil (AI-S), and at five years using AI-L, AI-S, centre-edge angle (CEA), and acetabular depth ratio (ADR). Each hip was classified based on published normative values for normal, borderline (1 to 2 standard deviations (SDs)), or dysplastic (> 2 SDs) based on sex, age, and laterality. Results. Of 202 infants who completed the protocol, 181 (90%) had two and five years’ follow-up radiographs. At two years, in 304 initially pathological hips, the prevalence of RAD (dysplastic) was 10% and RAD (borderline) was 30%. At five years, RAD (dysplastic) decreased to 1% to 3% and RAD (borderline) decreased to < 1% to 2%. On logistic regression, no variables were predictive of RAD at two years. Only AI-L at two years was predictive of RAD at five years (p < 0.001). If both hips were normal at two years’ follow-up (n = 96), all remained normal at five years. In those with bilateral borderline hips at two years (n = 21), only two were borderline at five years, none were dysplastic. In those with either borderline-dysplastic or bilateral dysplasia at two years (n = 26), three (12%) were dysplastic at five years. Conclusion. The majority of patients with RAD at two years post-brace treatment, spontaneously resolved by five years. Therefore, children with normal radiographs at two years post-brace treatment can be discharged. Targeted follow-up for those with abnormal AI-L at two years will identify the few who may benefit from surgical correction at five years’ follow-up. Cite this article: Bone Joint J 2024;106-B(7):744–750

Our aim was to determine whether abnormalities noted on MRI immediately after reduction for developmental dysplasia of the hip could predict the persistance of dysplasia and aid surgical planning. Scans of 13 hips in which acetabular dysplasia had resolved by the age of four years were compared with those of five which had required pelvic osteotomy for persisting dysplasia. The scans were analysed by two consultant musculoskeletal radiologists who were blinded to the outcome in each child. The postreduction scans highlighted a number of anatomical abnormalities secondary to developmental dysplasia of the hip, but statistical analysis showed that none were predictive of persisting acetabular dysplasia in the older child, suggesting that the factors which determine the long-term outcome were not visible on these images

Hereditary multiple exostoses is an autosomal dominant disorder characterised by multiple osteochondromata, most commonly affecting the forearm, knee and ankle. Osteochondromata of the proximal femur have been reported to occur in 30% to 90% of affected patients with coxa valga in 25%. Acetabular dysplasia is rare but has been described. This is the first report of a patient requiring surgical intervention. A girl was seen at the age of nine with hereditary multiple exostoses and when 12 developed bilateral pain in the groin. Radiographs showed severely dysplastic acetabula with less than 50% coverage of the femoral heads and widening of the medial joint space. Large sessile osteochondromata were present along the medial side of the femoral neck proximal to the lesser trochanter, with associated coxa valga. The case illustrates the importance of obtaining initial skeletal surveys in children with hereditary multiple exostoses to identify potential problems such as acetabular dysplasia and subluxation of the hip

Untreated acetabular dysplasia following treatment for developmental dysplasia of the hip (DDH) leads to early degenerative joint disease. Clinicians must accurately and reliably recognise dysplasia in order to intervene appropriately with secondary acetabular or femoral procedures. This study sought early predictors of residual dysplasia in order to establish empirically-based indications for treatment. DDH treated by closed or open reduction alone was reviewed. Residual hip dysplasia was defined according to the Severin classification at skeletal maturity. Future hip replacement in a subset of these patients was compared with the Severin classification. Serial measurements of acetabular development and subluxation of the femoral head were collected, as were the age at reduction, type of reduction, and Tonnis grade prior to reduction. These variables were used to predict the Severin classification. The mean age at reduction in 72 hips was 16 months (1 to 46). On the final radiograph, 47 hips (65%) were classified as Severin I/II, and 25 as Severin III/IV (35%). At 40 years after reduction, five of 43 hips (21%) had had a total hip replacement (THR). The Severin grade was predictive for THR. Early measurements of the acetabular index (AI) were predictive for Severin grade. For example, an AI of 35° or more at two years after reduction was associated with an 80% probability of becoming a Severin grade III/IV hip. This study links early acetabular remodelling, residual dysplasia at skeletal maturity and the long-term risk of THR. It presents evidence describing the diagnostic value of early predictors of residual dysplasia, and therefore, of the long-term risk of degenerative change

We carried out a morphometric analysis of acetabular dysplasia in patients with cerebral palsy requiring hip surgery using three-dimensional CT. We evaluated 54 hips in 27 patients. The contralateral normal hips of ten patients with unilateral Perthes’ disease were used as a control group. The acetabular defects were assessed qualitatively as anterior, posterior or global. Quantitative assessments were made using three-directional acetabular indices (anterosuperior, superolateral and posterosuperior) and measured by multiplanar reformation, from which we calculated the acetabular volume. In the qualitative study, posterior defects were most common in the subluxation group whereas global defects predominated in the dislocation group. In the quantitative study, all acetabular indices in both the subluxation and dislocation groups were higher than those in the control group and the superolateral indices showed a tendency to elevation in the dislocation group. The acetabular volume was largest in the control group, smallest in the dislocation group, and intermediate between the two in the subluxation group

We reviewed the medical records of 115 patients with 130 hips with developmental dysplasia with complete dislocation in the absence of a neuromuscular disorder, spontaneous reduction with a Pavlik harness, and a minimum of 14 years’ follow-up. The mean age at the time of harness application was 4.8 months (1 to 12) and the mean time spent in the harness was 6.1 months (3 to 12). A total of 108 hips (83.1%) were treated with the harness alone and supplementary surgery for residual acetabular dysplasia, as defined by an acetabular index > 30°, was performed in 22 hips (16.9%). An overall satisfactory outcome (Severin grade I or II) was achieved in 119 hips (91.5%) at a mean follow-up of 16 years (14 to 32) with a follow-up rate of 75%. Avascular necrosis of the femoral head was noted in 16 hips (12.3%), seven of which (44%) underwent supplementary surgery and nine (56%) of which were classified as satisfactory. The acetabular index was the most reliable predictor of residual acetabular dysplasia

Aims. Our aim was to assess the effectiveness of a protocol involving a standardised closed reduction for the treatment of children with developmental dysplasia of the hip (DDH) in maintaining reduction and to report the mid-term results. Methods. A total of 133 hips in 120 children aged less than two years who underwent closed reduction, with a minimum follow-up of five years or until subsequent surgery, were included in the study. The protocol defines the criteria for an acceptable reduction and the indications for a concomitant soft-tissue release. All children were immobilised in a short- leg cast for three months. Arthrograms were undertaken at the time of closed reduction and six weeks later. Follow-up radiographs were taken at six months and one, two and five years later and at the latest follow-up. The Tönnis grade, acetabular index, Severin grade and signs of osteonecrosis were recorded. Results. A total of 67 hips (51%) were Tönnis grade 3/4 hips. By 12 months, 20 reductions (15%) had not been maintained, and these required open reduction. In all, 55% of these were Severin 1; the others were Severin 2, due to minor acetabular dysplasia. Of the 113 successful closed reductions, 98 hips (87%) were Severin 1. Surgery for residual DDH was offered for ten hips. Osteonecrosis was seen in 32 hips (29%) but was transient in 28. In total, two children (1.5%) had severe osteonecrosis. Bilateral dislocations were significantly more likely to fail and most Tönnis 4 hips failed. Conclusion. Closed reduction, with concomitant adductor and psoas release when required and the use of a short leg plaster of Paris cast for three months, can produce good mid-term results in children with DDH aged less than two years. This protocol is not recommended for Tönnis 4 hips. Cite this article: Bone Joint J 2016;98-B:1548–53

We treated eight dysplastic acetabula in six skeletally mature patients with Down’s syndrome by a modified Bernese periacetabular osteotomy. The mean age at the time of surgery was 16.5 years (12.8 to 28.5). Mean length of follow-up was five years (2 to 10.4). Pre-operatively the mean (Tönnis) acetabular angle was 28°, the centre-edge angle was −9°, and the extrusion index was 60%; post-operatively they were 3°, 37°, and 17%, respectively. Two patients with post-operative (Tönnis) acetabular angles > 10° developed subluxation post-operatively and required secondary varus derotation femoral osteotomies. Another patient developed a late labral tear which was treated arthroscopically. All eight hips remain clinically stable, and are either asymptomatic or symptomatically improved. These results suggest that the modified Bernese periacetabular osteotomy can be used successfully in the treatment of acetabular dysplasia in patients with Down’s syndrome

The practice of regular radiological follow-up of infants with a positive family history of developmental dysplasia of the hip is based on the widespread belief that primary acetabular dysplasia is a genetic disorder which can occur in the absence of frank subluxation or dislocation. We reviewed all infants who were involved in our screening programme for developmental dysplasia of the hip, between November 2002 and January 2004, and who had a normal clinical and ultrasound examination of the hip at six to eight weeks of age, but who, because of a family history of developmental dysplasia of the hip, had undergone further radiography after an interval of 6 to 12 months. The radiographs of 89 infants were analysed for signs of late dysplasia of the hip and assessed independently by three observers to allow for variability of measurement. There were 11 infants (11%) lost to follow-up. All the patients had normal radiographs at the final follow-up and none required any intervention. We therefore question the need for routine radiological follow-up of infants with a positive family history of developmental dysplasia of the hip, but who are normal on clinical examination and assessment by ultrasound screening when six to eight weeks old

Aims

Brace treatment is the cornerstone of managing developmental dysplasia of the hip (DDH), yet there is a lack of evidence-based treatment protocols, which results in wide variations in practice. To resolve this, we have developed a comprehensive nonoperative treatment protocol conforming to published consensus principles, with well-defined a priori criteria for inclusion and successful treatment.

Aims

Early detection of developmental dysplasia of the hip (DDH) is associated with improved outcomes of conservative treatment. Therefore, we aimed to evaluate a novel screening programme that included both the primary risk factors of breech presentation and family history, and the secondary risk factors of oligohydramnios and foot deformities.

Aims

Developmental dysplasia of the hip (DDH) can be managed effectively with non-surgical interventions when diagnosed early. However, the likelihood of surgical intervention increases with a late presentation. Therefore, an effective screening programme is essential to prevent late diagnosis and reduce surgical morbidity in the population.

Aims

The aim of this study was to identify the information topics that should be addressed according to the parents of children with developmental dysplasia of the hip (DDH) in the diagnostic and treatment phase during the first year of life. Second, we explored parental recommendations to further optimize the information provision in DDH care.

Aims

There is no consensus regarding optimum timing and frequency of ultrasound (US) for monitoring response to Pavlik harness (PH) treatment in developmental dysplasia of the hip (DDH). The purpose of our study was to determine if a limited-frequency hip US assessment had an adverse effect on treatment outcomes compared to traditional comprehensive US monitoring.

Aims

The most important complication of treatment of developmental dysplasia of the hip (DDH) is avascular necrosis (AVN) of the femoral head, which can result in proximal femoral growth disturbances leading to pain, dysfunction, and eventually to early onset osteoarthritis. In this study, we aimed to identify morphological variants in hip joint development that are predictive of a poor outcome.

Aims

We aimed to determine hip-related quality of life and clinical findings following treatment for neonatal hip instability (NHI) compared with age- and sex-matched controls. We hypothesized that NHI would predispose to hip discomfort in long-term follow-up.

Aims

The diagnosis of developmental dysplasia of the hip (DDH) is challenging owing to extensive variation in paediatric pelvic anatomy. Artificial intelligence (AI) may represent an effective diagnostic tool for DDH. Here, we aimed to develop an anteroposterior pelvic radiograph deep learning system for diagnosing DDH in children and analyze the feasibility of its application.

Aims

The goal of closed reduction (CR) in the treatment of developmental dysplasia of the hip (DDH) is to achieve and maintain concentricity of the femoral head in the acetabulum. However, concentric reduction is not immediately attainable in all hips and it remains controversial to what degree a non-concentric reduction is acceptable. This prospective study is aimed at investigating the dynamic evolution of the hip joint space after CR in DDH using MRI.

Aims

The purpose of this study was to analyze the incidence of the different ultrasound phenotypes of developmental dysplasia of the hip (DDH), and to determine their subsequent course.

The medial approach for the treatment of children with developmental dysplasia of the hip (DDH) in whom closed reduction has failed requires minimal access with negligible blood loss. In the United Kingdom, there is a preference for these children to be treated using an anterolateral approach after the appearance of the ossific nucleus. In this study we compared these two protocols, primarily for the risk of osteonecrosis.

Data were gathered prospectively for protocols involving the medial approach (26 hips in 22 children) and the anterolateral approach (22 hips in 21 children) in children aged <  24 months at the time of surgery. Osteonecrosis of the femoral head was assessed with validated scores. The acetabular index (AI) and centre–edge angle (CEA) were also measured.

The mean age of the children at the time of surgery was 11 months (3 to 24) for the medial approach group and 18 months (12 to 24) for the anterolateral group, and the combined mean follow-up was 70 months (26 to 228). Osteonecrosis of the femoral head was evident or asphericity predicted in three of 26 hips (12%) in the medial approach group and four of 22 (18%) in the anterolateral group (p = 0.52). The mean improvement in AI was 8.8° (4° to 12°) and 7.9° (6° to 10°), respectively, at two years post-operatively (p = 0.18). There was no significant difference in CEA values of affected hips between the two groups.

Children treated using an early medial approach did not have a higher risk of developing osteonecrosis at early to mid-term follow-up than those treated using a delayed anterolateral approach. The rates of acetabular remodelling were similar for both protocols.

Cite this article: Bone Joint J 2014;96-B:406–13.

We describe our experience in the reduction of dislocation of the hip secondary to developmental dysplasia using ultrasound-guided gradual reduction using flexion and abduction continuous traction (FACT-R). During a period of 13 years we treated 208 Suzuki type B or C complete dislocations of the hip in 202 children with a mean age of four months (0 to 11). The mean follow-up was 9.1 years (five to 16). The rate of reduction was 99.0%. There were no recurrent dislocations, and the rate of avascular necrosis of the femoral head was 1.0%. The rate of secondary surgery for residual acetabular dysplasia was 19.2%, and this was significantly higher in those children in whom the initial treatment was delayed or if other previous treatments had failed (p = 0.00045). The duration of FACT-R was significantly longer in severe dislocations (p = 0.001) or if previous treatments had failed (p = 0.018).

This new method of treatment is effective and safe in these difficult cases and offers outcomes comparable to or better than those of standard methods.

Cite this article: Bone Joint J 2015;97-B:405–11.

Salter innominate osteotomy is an effective reconstructive procedure for the treatment of developmental dysplasia of the hip (DDH), but some children have a poor outcome at skeletal maturity. In order to investigate factors associated with an unfavourable outcome, we assessed the development of the contralateral hip. We retrospectively reviewed 46 patients who underwent a unilateral Salter osteotomy at between five and seven years of age, with a mean follow-up of 10.3 years (7 to 20). The patients were divided into three groups according to the centre–edge angle (CEA) of the contralateral hip at skeletal maturity: normal (> 25°, 22 patients), borderline (20° to 25°, 17 patients) and dysplastic (<  20°, 7 patients). The CEA of the affected hip was measured pre-operatively, at eight to nine years of age, at 11 to 12 years of age and at skeletal maturity. The CEA of the affected hip was significantly smaller in the borderline and dysplastic groups at 11 and 12 years of age (p = 0.012) and at skeletal maturity (p = 0.017) than in the normal group. Severin group III was seen in two (11.8%) and four hips (57.1%) of the borderline and dysplastic groups, respectively (p < 0.001).

Limited individual development of the acetabulum was associated with an unfavourable outcome following Salter osteotomy.

Cite this article: Bone Joint J 2014;96-B:1419–23.

In 1994 a cerebral palsy (CP) register and healthcare programme was established in southern Sweden with the primary aim of preventing dislocation of the hip in these children.

The results from the first ten years were published in 2005 and showed a decrease in the incidence of dislocation of the hip, from 8% in a historical control group of 103 children born between 1990 and 1991 to 0.5% in a group of 258 children born between 1992 and 1997. These two cohorts have now been re-evaluated and an additional group of 431 children born between 1998 and 2007 has been added.

By 1 January 2014, nine children in the control group, two in the first study group and none in the second study group had developed a dislocated hip (p < 0.001). The two children in the first study group who developed a dislocated hip were too unwell to undergo preventive surgery. Every child with a dislocated hip reported severe pain, at least periodically, and four underwent salvage surgery. Of the 689 children in the study groups, 91 (13%) underwent preventive surgery.

A population-based hip surveillance programme enables the early identification and preventive treatment, which can result in a significantly lower incidence of dislocation of the hip in children with CP.

Cite this article: Bone Joint J 2014; 96-B:1546–52.

The outcome of one-stage bilateral open reduction through a medial approach for the treatment of developmental dysplasia of the hip in children under 18 months was studied in 23 children, 18 girls and five boys. Their mean age at operation was 10.1 months (6 to 17) and the mean follow-up was 5.4 years (3 to 8).

Acceptable clinical and radiological results were achieved in 44 (95.7%) and 43 (93.5%) of 46 hips, respectively. Excellent results were significantly evident in patients younger than 12 months, those who did not require acetabuloplasty, those whose ossific nucleus had appeared, and in those who did not develop avascular necrosis.

One-stage bilateral medial open reduction avoids the need for separate procedures on the hips and has the advantages of accelerated management and shorter immobilisation and rehabilitation than staged operations.

In order to treat painful subluxation or dislocation secondary to cerebral palsy, 11 patients (12 hips) underwent combined femoral and Chiari pelvic osteotomies with additional soft-tissue releases at a mean age of 14.1 years (9.1 to 17.8). Relief of pain, improvement in movement of the hip, and in sitting posture, and ease of perineal care were recorded in all, and were maintained at a mean follow-up of 13.1 years (8 to 17.5). The improvement in general mobility was marginal, but those who were able to walk benefited the most.

The radiological measurements made before operation were modified afterwards to use the lateral margin of the neoacetabulum produced by the pelvic osteotomy. The radiological migration index improved from a mean of 80.6% (61% to 100%) to 13.7% (0% to 33%) (p < 0.0001). The mean changes in centre edge angle and Sharp’s angle were 72° (56° to 87°; p < 0.0001) and 12.3° (9° to 15.6°; p < 0.0001), respectively. Radiological evidence of progressive arthritic change was seen in one hip, in which only a partial reduction had been achieved, and there was early narrowing of the joint space in another. Painless heterotopic ossification was observed in one patient with athetoid quadriplegia. In seven hips the lateral Kawamura approach, elevating the greater trochanter, provided exposure for both osteotomies and allowed the construction of a dome-shaped iliac osteotomy, while protecting the sciatic nerve.

Proximal femoral varus osteotomy improves the biomechanics of the hip and can stimulate normal acetabular development in a dysplastic hip. Medial closing wedge osteotomy remains the most popular technique, but is associated with shortening of the ipsilateral femur.

We produced a trigonometric formula which may be used pre-operatively to predict the resultant leg length discrepancy (LLD). We retrospectively examined the influence of the choice of angle in a closing wedge femoral osteotomy on LLD in 120 patients (135 osteotomies, 53% male, mean age six years, (3 to 21), 96% caucasian) over a 15-year period (1998 to 2013). A total of 16 of these patients were excluded due to under or over varus correction. The patients were divided into three age groups: paediatric (< 10 years), adolescent (10 to 16 years) and adult (> 16 years). When using the same saw blades as in this series, the results indicated that for each 10° of angle of resection the resultant LLD equates approximately to multiples of 4 mm, 8 mm and 12 mm in the three age groups, respectively.

Statistical testing of the 59 patients who had a complete set of pre- and post-operative standing long leg radiographs, revealed a Pearson’s correlation coefficient for predicted versus radiologically observed shortening when using a wedge of either 10° or 20° of 0.93 (p <  0.001). The 95% limits of agreement from the Bland–Altman analysis for this subgroup were –3.5 mm to +3.3 mm. It has been accepted that a 10 mm discrepancy is clinically acceptable.

This study identified a geometric model that provided satisfactory accuracy when using specific saw blades of known thicknesses for this formula to be used in clinical practice.

Cite this article: Bone Joint J 2014;96-B:1124–9

This study compares the initial outcomes of minimally invasive techniques for single-event multi-level surgery with conventional single-event multi-level surgery. The minimally invasive techniques included derotation osteotomies using closed corticotomy and fixation with titanium elastic nails and percutaneous lengthening of muscles where possible. A prospective cohort study of two matched groups was undertaken. Ten children with diplegic cerebral palsy with a mean age of ten years six months (7.11 to 13.9) had multi-level minimally invasive surgery and were matched for ambulatory level and compared with ten children with a mean age of 11 years four months (7.9 to 14.4) who had conventional single-event multi-level surgery. Gait kinematics, the Gillette Gait Index, isometric muscle strength and gross motor function were assessed before and 12 months after operation.

The minimally invasive group had significantly reduced operation time and blood loss with a significantly improved time to mobilisation. There were no complications intra-operatively or during hospitalisation in either group. There was significant improvement in gait kinematics and the Gillette Gait Index in both groups with no difference between them. There was a trend to improved muscle strength in the multi-level group. There was no significant difference in gross motor function between the groups.

We consider that minimally invasive single-event multi-level surgery can be achieved safely and effectively with significant advantages over conventional techniques in children with diplegic cerebral palsy.

We carried out a morphometric analysis of the acetabulum following Dega osteotomy in patients with cerebral palsy using three-dimensional CT. We assessed 17 acetabula in 12 patients with instability of the hip. A Dega osteotomy and varus derotation femoral osteotomy were performed in all 17 hips. Three-dimensional CT scans were taken before and approximately one year after operation. Acetabular cover was evaluated using anterosuperior, superolateral and posterosuperior acetabular indices, and the change in the acetabular volume was calculated. Inter- and intra-observer reliability was assessed using the intraclass correlation coefficient. After the osteotomy, the anterosuperior, superolateral and posterosuperior cover had improved significantly towards the value seen in a control group. The mean acetabular volume increased by 68%.

The results of a functional, clinical and radiological study of 30 children (60 hips) with whole-body cerebral palsy were reviewed at a mean follow-up of 10.2 years (9.5 to 11). Correction of windsweep deformity of the hips was performed by bilateral simultaneous combined soft-tissue and bony surgery at a mean age of 7.7 years (3.1 to 12.2).

We were able to recall 22 patients; five had died of unrelated causes and three were lost to follow-up. Evaluation involved interviews with patients/carers and clinical and radiological examination.

The gross motor functional classification system was used to assess overall motor function and showed improvement in seven patients. Of the 12 patients thought to have pain pre-operatively, only one had pain post-operatively. Improved handling was reported in 18 of 22 patients (82%). Those with handling problems were attributed by the carers to growth of the patients. All patients/carers considered the procedure worthwhile. The range of hip movements improved, and the mean windsweep index improved from 50 pre-operatively to 36 at follow-up.

The migration percentage and centre-edge angle were assessed on plain radiographs. Radiological containment improved, the mean migration percentage improved from 50 pre-operatively to 20 at follow-up and the mean centre-edge angle improved from −5° to 29°.

No statistical difference was noted between the three-year and ten-year follow-up results, indicating that the improvements in clinical and radiological outcome had been maintained.

We present the results of treatment of developmental dysplasia of the hip in infancy with the Pavlik harness using a United Kingdom screening programme with ultrasound-guided supervision. Initially, 128 consecutive hips in 77 patients were reviewed over a 40-month period; 123 of these were finally included in the study. The mean age of the patients at the start of treatment was five weeks (1 to 12). All hips were examined clinically and monitored with ultrasound scanning. Failure of treatment was defined as an inability to maintain reduction with the harness. All hips diagnosed with dysplasia or subluxation but not dislocation were managed successfully in the harness. There were 43 dislocated hips, of which 39 were reducible, but six failed treatment in the harness. There were four dislocated but irreducible hips which all failed treatment in the harness. One hip appeared to be successfully treated in the harness but showed persistent radiological dysplasia at 12 and 24 months. Grade 1 avascular necrosis was identified radiologically in three patients at 12 months.

We reviewed the evidence for hip surveillance in children with cerebral palsy from the published literature.

Publications were identified using the Cochrane controlled trials register, the MEDLINE, EMBASE and CINAHL databases and by hand searching key journals and their references. Studies were included if they reported the frequency, associated risk factors or surveillance measures undertaken to identify subluxation or dislocation of the hip in children with cerebral palsy. Assessment of the quality of the methodology was undertaken independently by two researchers.

Four studies described the natural history, incidence and risk factors for dislocation of the hip. Two reported their surveillance results. Approximately 60% of children who were not walking by five years of age were likely to develop subluxation of the hip, with the greatest risk in those with severe neurological involvement. The introduction of surveillance programmes allowed earlier identification of subluxation and reduced the need for surgery on dislocated hips.

Surveillance can identify children most at risk of subluxation using radiological methods which are widely available.

In 1994, a register for cerebral palsy and a health-care programme were started in southern Sweden with the aim of preventing dislocation of the hip in children with cerebral palsy. It involved all children with cerebral palsy born in 1992 or later.

None of the 206 affected children born between 1992 and 1997 has developed a dislocation following the introduction of the prevention programme. Another 48 children moved into the area and none developed any further dislocation. Of the 251 children with cerebral palsy, aged between five and 11 years, living in the area on January 1, 2003, only two had a dislocated hip. One boy had moved into the area at age of nine with a dislocation and a girl whose parents chose not to participate in the programme developed bilateral dislocation. One boy, whose condition was considered to be too poor for preventative surgery, developed a painful dislocation of the hip at the age of five years and died three years later.

Eight of 103 children in a control group, consisting of all children with cerebral palsy living in the area between 1994 and 2002, and born between 1990 and 1991, developed a dislocation of the hip before the age of six years.

The decreased incidence of dislocation after the introduction of the prevention programme was significant (p < 0.001). Dislocation of the hip in cerebral palsy remains a serious problem, and prevention is important. Our screening programme and early intervention when lateral displacement of the femoral head was detected appear to be successful.

In late developmental dysplasia of the hip in childhood, the deformed dysplastic acetabulum is malaligned and has lost its shape due to pressure from the subluxed femoral head. The outer part of the acetabulum involves the upper part of the original acetabulum, thereby giving a bipartite appearance. A clear edge separates the outer from inner part which represents the lower part of the original acetabulum and has no direct contact with the femoral head.

Combined pelvic osteotomy (CPO) using a Lance acetabuloplasty with either a Salter or a Pemberton procedure restores the original shape and realigns the acetabulum. A total of 20 children (22 hips), with a mean age of 46 months (28 to 94) at primary operation underwent CPO with follow-up for between 12 and 132 months.

In each case concentric stable reduction with good acetabular cover was achieved and maintained throughout the period of follow-up.

This prospective cohort study aimed to investigate the relationship between developmental dysplasia of the hip and mode of delivery in 571 consecutive breech infants using a modified Graf’s static morphological method to grade the severity of dysplasia.

In this group, 262 infants were born by planned Caesarian section, 223 by emergency section and 86 vaginally. Taking all grades of hip dysplasia into account (Graf types II, III and IV), there was no statistical difference in the incidence of dysplasia between the groups (elective section 8.4%, emergency section 8.1% and vaginal delivery 7.0%). However, when cases with Graf type II dysplasia, which may represent physiological immaturity, were excluded, the rate of type III and IV hips, which we consider to be clinically relevant, increased in the vaginally delivered group (4.7%) compared with the elective section group (1.1%), with a relative risk of approximately 1:4 (95% confidence interval 1.03 to 15.91). No difference was observed between the emergency and elective section groups, or between the emergency section and vaginally delivered groups.

This study supports previous published work, with the added value that the diagnoses were all confirmed by ultrasound.

We prospectively studied the benefits and risks of prolonged treatment with the Pavlik harness in infants with idiopathic developmental dysplasia of the hip. Bracing was continued as long as abduction improved. It was started at a mean age of four months (1 to 6.9). Outcome measures were the number of successful reductions, the time to reduction, the acetabular index and evidence of avascular necrosis at follow-up at one year.

In 50 infants with 62 subluxated and dislocated hips (42 Graf type III and 20 type IV), 37 were reduced successfully with a mean time to reduction of 13.4 weeks (sd 6.8). Bracing was successful in 31 type-III (73.8%) and in only six type-IV hips (20%, p = 0.002). Avascular necrosis was seen in ten hips.

Prolonged treatment with the Pavlik harness for developmental dysplasia of the hip over the age of one month can be beneficial in type-III hips, but it is unclear as to whether this is the optimal treatment, since it may postpone the need for closed or open reduction to a more unfavourable age. The use of the Pavlik harness in type-IV hips in this age group is questionable, but if used, prolonged bracing is not advised.

In a prospective study over 11 years we assessed the relationship between neonatal deformities of the foot and the presence of ultrasonographic developmental dysplasia of the hip (DDH). Between 1 January 1996 and 31 December 2006, 614 infants with deformities of the foot were referred for clinical and ultrasonographic evaluation. There were 436 cases of postural talipes equinovarus deformity (TEV), 60 of fixed congenital talipes equinovarus (CTEV), 93 of congenital talipes calcaneovalgus (CTCV) and 25 of metatarsus adductus.

The overall risk of ultrasonographic dysplasia or instability was 1:27 in postural TEV, 1:8.6 in CTEV, 1:5.2 in CTCV and 1:25 in metatarsus adductus.

The risk of type-IV instability of the hip or irreducible dislocation was 1:436 (0.2%) in postural TEV, 1:15.4 (6.5%) in CTCV and 1:25 (4%) in metatarsus adductus. There were no cases of hip instability (type IV) or of irreducible dislocation in the CTEV group.

Routine screening for DDH in cases of postural TEV and CTEV is no longer advocated. The former is poorly defined, leading to the over-diagnosis of a possibly spurious condition. Ultrasonographic imaging and surveillance of hips in infants with CTCV and possibly those with metatarsus adductus should continue.

Since September 1964, neonates born in New Plymouth have undergone clinical examination for instability of the hip in a structured clinical screening programme. Of the 41 563 babies born during this period, 1639 were diagnosed as having unstable hips and 663 (1.6%) with persisting instability were splinted, five of which failed. Also, three unsplinted hips progressed to congenital dislocation, and there were four late-presenting (walking) cases, giving an overall failure rate of 0.29 per 1000 live births, with an incidence of late-walking congenital dislocation of the hip of 0.1 per 1000 live births.

This study confirms that clinical screening for neonatal instability of the hip by experienced orthopaedic examiners significantly reduces the incidence of late-presenting (walking) congenital dislocation of the hip.

The Salter innominate osteotomy has been used successfully for many years in the treatment of developmental dysplasia of the hip. One of its main drawbacks is the need for internal fixation with pins and their subsequent removal. We describe a modification of this osteotomy that does not require pin fixation and secondary removal. We retrospectively reviewed 114 hips in 94 patients who had been operated on by a single surgeon. An oblique rather than the original horizontal osteotomy was used without internal fixation. There were 80 female and 14 male patients. The mean age at operation was 25 months (18 to 84) and the mean follow-up was 30 months (12 to 88). Most patients required additional open reduction and capsuloplasty. The mean pre-operative acetabular index was 37.9° (24° to 54°), which decreased to 19.9° (7° to 29°) in the immediate post-operative period, and improved to 14.6° (5° to 25°) at the final follow-up (student’s t-test, p < 0.0001).

We believe that by changing the direction of the osteotomy line, it is possible to avoid pin fixation. The radiological outcomes are comparable to those of the original technique, but longer follow-up will be necessary.

We wished to establish whether delivery by Caesarean section influenced the incidence of developmental dysplasia of the hip in term breech infants compared with those delivered vaginally. We used maternal charts, singleton term breech presentation, mode of delivery and incidence of developmental dysplasia of the hip for births between January 1997 and October 2002.

During the study period 46 089 infants were born. We analysed a total of 941 breech infants of whom 756 were delivered by Caesarean section (515 pre-labour, 241 intrapartum) and 185 vaginally. The incidence of developmental dysplasia of the hip according to the mode of delivery was 19 of 515 (3.69%) following pre-labour Caesarean section, 16 of 241 (6.64%) for intrapartum Caesarean section and 15 of 185 (8.11%) after vaginal delivery. There was a lower incidence of developmental dysplasia of the hip among those infants delivered by elective Caesarean section compared with those delivered vaginally (p < 0.02). These results demonstrate a significantly lower incidence of developmental dysplasia of the hip in term singleton breech births delivered by elective, pre-labour Caesarean section and suggest that labour and delivery influence hip stability in predisposed infants.

A total of 47 non-walking patients (52 hips) with severe cerebral palsy and with a mean age of 14 years, (9 to 27) underwent a Dega-type pelvic osteotomy after closure of the triradiate cartilage, together with a derotation varus-shortening femoral osteotomy and soft-tissue correction for hip displacement which caused pain and/or difficulties in sitting. The mean follow-up was 48 months (12 to 153). The migration percentage improved from a pre-operative mean of 70% (26% to 100%) to 10% (0% to 100%) post-operatively. In five hips the post-operative migration percentage was greater than 25%, which was associated with continuing pain in two patients. Three patients had persistent hip pain and a migration percentage less than 25%. In five hips a fracture through the acetabulum occurred, and in another there was avascular necrosis of the superior acetabular segment, but these had no adverse effect on functional outcome. We conclude that it is possible to perform a satisfactory pelvic osteotomy of this type in these patients after the triradiate cartilage has been closed.

We treated 15 hips (15 patients) with developmental dysplasia by a single-stage combination of open reduction through a medial approach and innominate osteotomy. The mean age of the patients at the time of operation was 20 months (13 to 30). The mean follow-up period was 9.6 years (4 to 14).

At the final follow-up, 14 hips were assessed clinically as excellent and one hip as good. Radiologically, ten hips were rated as class I, four as class II and one as class III according to the criteria of Severin. No avascular necrosis was seen. No patient required subsequent surgery. Our results indicate that satisfactory results can be obtained with the single-stage combination of open reduction by the medial approach and innominate osteotomy for developmental dysplasia of the hip in a selected group of children older than 12 months. To our knowledge, no similar combined technique has been previously reported.

We present a retrospective study of 27 patients treated by callus distraction using a unilateral external fixator of our own design for nonunion with bone loss and shortening of the femur caused by suppurative osteomyelitis. The unilateral external fixator was used either alone or in combination with an intramedullary nail. The mean age of the patients was 13.6 years (8 to 18). The fixator was used alone in 13 patients and with an intramedullary nail in 14. The bone results at a mean follow-up of 88 months (37 to 144) were excellent in 16 patients and good in 11.

The functional results were excellent in 18 patients and good in nine. However, four patients still had draining sinuses at the latest follow-up. A residual deformity greater than 7° was present in seven femora, but this did not adversely affect function or require further treatment.